Question on Tune Up Timing

https://griffinbmiu621.summitquill.com/posts/a-comfort-experts-checklist-for-ac-tune-ups-and-fewer-north-fort-worth-ac-repairs

Question on Tune Up Timing Does anyone know if spring or fall is better for a tune-up? Not sure when it makes the most sense for an older system in Summerfields, since the AC works hardest in summer but the furnace matters in winter