C1 and C2 are EOLed. I read somewhere (here?) that their design was problematic and the maintenance was expensive :(
C1 (ARM32 dedicated) was still available recently when I checked last time. Existing customers' instances are definitely still running, used one today.
I just wish they would let me run Alpine Linux on the DEV1-S. Its available for the more expensive DEV1 instances, but they obviously don't want me taking full advantage of the meager resources the DEV1-S offers.
Of course if you do it under time is money principle that's a trainwreck compared to using their image. But if you do it for the fun of it...