(1) Add secondary mx to your domain.
(2) create user on new host setup same catchall account as was on old host
(3) stop incoming/outgoing cron (remove is best) on old host
(4) export the db on old host and import on new host
(5) scp all files from old to new (presume ssh access is available as). Ensure all file ownership of new host are correct.
(6) edit config changes (with respect to absolute paths) in one of those files (can;t recall as been tooo long since i last touched gmail) -- perhaps someone from GT can chip in here.
(7) remove primary mx record from dns. Wouldn't hurt if the catchall account data is synced again.
(8) setup incoming.outgoing cron

Just top of the head so if something is missed others can add to above.

Thanks
HyTC
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