Wife and I just applied for another Covid extension at Satun immigration office. Our current extension ends on April 16th.
We received an under consideration stamp dated _May_ 1st. We were expecting something like April 7th, which would be 15 days from now. We were also told we can come back earlier than May 1st but didn't mention how much earlier. When I asked if April 7th would be ok she said yes. She also told is we would receive Covid extension to June 15th. All good and even easier than in Chiang Mai.
TLDR : Answer Summary
The user applied for a Covid visa extension at the Satun immigration office, with their current extension set to expire on April 16th. They received an under consideration stamp that is dated May 1st, despite expecting it to be processed around April 7th. The immigration official mentioned they could return earlier and confirmed that the extension would be valid until June 15th.