Is it supposed to be all smooth sailing launching gp2 instances from standard snapshots and vice versa ? It may be just me but I've had really weird and seriou

Is it supposed to be all smooth sailing launching gp2 instances from standard snapshots and vice versa ? It may be just me but I've had really weird and serious new errors today in us-east-1 launching new instances, or even starting previously stopped ones with no changes to the instance whatsoever ! General slowness, "reachability" health check failing, with the system log showing that the kernel couldn't be uncompressed, maybe because the bootloader couldn't find the root device in the first place ? I'm not using custom kernels at all. The timing is too strange for it to be a coincidence, but nothing on the AWS status page.