Could you just temporarily lift the mail size limit for the transition to Yahoo?

@Turbo07 

I'm checking my mailbox to find messages over 25MB.  I don't know if that's Real Binary MB (1048576) or Marketing MB  (1000000).  And of course the webmail interface has no way to search based on size, so I'm relying on Thunderbird/Outlook to do that.  In some cases they can't agree on how big the attachments are - are you using binary size or MIME-encoded size?

I have a relative handful of messages that shouldn't be there if you were enforcing a 25MB limit before.  Couldn't you just lift it to something like 50MB for the transfer and then knock it back down afterward?  It's a real pain to have to search for and then save these messages elsewhere over an arbitrary limit.

Unfortunately that's not a possibility.  I believe that Yahoo! Mail also uses the 25MB limit.

When mail servers contact Comcast.net addresses, one of the status codes the server returns is "250-SIZE 36700160". 

36,700,160 appears to be 35*1024*1024, or 35 * 2^20. So 35 "real" (binary) megabytes. 

When mail servers contact Yahoo.com addresses, one of the status codes the server returns is "250-SIZE 41943040". 

41,943,040 appears to be 40*1024*1024, or 40 * 2^20. So 40 "real" (binary) megabytes, even though as @Again stated and https://help.yahoo.com/kb/SLN5673.html confirms, Yahoo says the limit is 25 megabytes. 

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