Retirement Ext CM…time to appear these days?

(Chiangmai Immigration)
Hi there
My retirement extension ends Sept 28.
A friend’s ends Sept 14th.
My life companion has previously paid someone from her hospital she works 500bt to go and pick up the number early.
I think it entailed two visits to Airport IMM, one early and another to get the appointment time a wee bit later.
I believe one can now do the extension 45 days early?
IF so, friend and I think maybe we could share one person to go and get an appointment for both of us for the same day, give her a bit more as incentive.
1. Think this would be OK?
2. Presume it’s Promenada?
3. We’ve heard the crazy-early times have become more civilised. What time should she go to be safe?
4. Want to make it simple and pain free as poss about times etc……last time she woke up life companion about three times on phone……to avoid this what would be her instruction sheet?
thank you for help!