Hi H.,

This is a user-to-user forum, so for an official answer you'd best contact Ritlabs by e-mail.

a) Gmail (Google) is probably the world's most popular provider, The Bat has always supported it and Ritlabs has always updated their software whenever Gmail quircks made that necessary, so I wouldn't expect any changes there. However, Gmail is also the most unpredictable and obstinate provider so I doubt that any publisher of mail client software would 'guarantee' Gmail support (actually, standard software rarely ever comes with any guarantees -- it is licensed 'as is' because the diversity of platforms and the dependence on hardware, drivers and an operating system that all work correctly make that impossible).

b) and c) shouldn't pose any problems either, but I wonder what would happen if your ex-partner would try to upgrade from the same license. I don't know if Ritlabs actually keep records of which old licenses have been upgraded, but if they do, I suppose that only one of you could purchase the upgrade.