Note: I used to run Source Merits down, and the sprees did try to nibble into the personal merit allocation. With the last merit allowance increase I seem to only be able to do so budget the spree with Source Merits. They are now low enough though to, perhaps, start depleting the personal Merits in a week or two though regular usage (let’s see) …
For the records, my Merit band is muted between 1:00 AM and 7:00 AM (you all know which timezone I am referring to), so doing a merits spree during these hours wouldn't activate it. You won't be able to wake me up in the middle of a night and make me tush to the keyboard to beat @neuroticfish to it!