Mp3tag v2.48 deleted all (unrecognized) atom data from M4A audio files. Since v2.49, it keeps atom data, but does not have ability to edit them.

I wish Mp3tag can. I have some "hard-tagged" M4A audio files, and I really want to edit/or remove atom from them.
Using the "Remove Tag" command is not working for atoms.

Example: Here is information extracted from a M4A file via MediaInfo program.

Unrecognized atoms by Mp3tag are in bold.

CODE
General
Complete name                            : ***\10 I Won't Last a Day Without You.m4a
Format                                   : MPEG-4
Format profile                           : Apple audio with iTunes info
Codec ID                                 : M4A
File size                                : 7.79 MiB
Duration                                 : 3mn 52s
Overall bit rate mode                    : Variable
Overall bit rate                         : 281 Kbps
Album                                    : A song for you
Album/Performer                          : Carpenters
Part/Position                            : 1
Part/Total                               : 1
Track name                               : I won't last a day without you
Track name/Position                      : 10
Track name/Total                         : 13
Performer                                : Carpenters
Genre                                    : Rock
Recorded date                            : UTC 1972-06-01 00:00:00
Tagged date                              : UTC 2011-10-02 16:41:12
[b]Writing application                      : [url="http://Http://www.indetime.com"]Http://www.indetime.com[/url][/b]
Copyright                                : ℗ 1972 UMG Recordings, Inc.
Cover                                    : Yes
apID                                     : alecbudow@hotmail.com
[b]cnID                                     : 357935
rtng                                     : 0
atID                                     : 117982008
plID                                     : 357947
geID                                     : 21
sfID                                     : 143441
akID                                     : 0
stik                                     : 1[/b]
purd                                     : 2011-10-02 07:47:52
[b]soal                                     : Song for You (Original Recording Remastered)
xid                                      : Universal:isrc:USAM17200061
flvr                                     : 2:256[/b]
iTunMOVI                                 : <?xml version="1.0" encoding="UTF-8"?> / <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> / <plist version="1.0"> / <dict> /     <key>asset-info</key> /     <dict> /         <key>file-size</key> /         <integer>8170517</integer> /         <key>flavor</key> /         <string>2:256</string> /     </dict> / </dict> / </plist>
[b]©url                                     : [url="http://www.indetime.com"]http://www.indetime.com[/url]
furl                                     : [url="http://www.indetime.com"]http://www.indetime.com[/url]
aurl                                     : [url="http://www.indetime.com"]http://www.indetime.com[/url]
surl                                     : [url="http://www.indetime.com"]http://www.indetime.com[/url]
rnam                                     : [url="http://Http://www.indetime.com"]Http://www.indetime.com[/url]
rurl                                     : [url="http://www.indetime.com"]http://www.indetime.com[/url]
burl                                     : [url="http://www.indetime.com"]http://www.indetime.com[/url]
tvsn                                     : 0
tves                                     : 0
rati                                     : (Binary)[/b]

Audio
ID                                       : 1
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : LC
Codec ID                                 : 40
Duration                                 : 3mn 52s
Bit rate mode                            : Variable
Bit rate                                 : 256 Kbps
Maximum bit rate                         : 279 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 44.1 KHz
Compression mode                         : Lossy
Stream size                              : 7.22 MiB (93%)
Language                                 : English
Tagged date                              : UTC 2011-10-02 16:41:12


We can remove atom from files by using AtomicParsley, but it's command-line program; too hard for average users.
Thank you for reading.