Alternating order of operation of two outputs

Good Morning,

I am working on my first mildly complex program with LOGO!, I am using a 4-20 ma pressure transducer for a compressed air system, consisting of two air compressors. I call them Compressor A and Compressor B

• compressor A starts @ 130 PSI
• if pressure continues to drop then compressor B starts @120 PSI

up to this point the system works as intended, however I want to alternate the order of those compressors. I have some ideas but not a good way to actually implement this,

• one option that occurs is to use RTC so every 24 hours the order will invert. 
• another option is to use a counter, every X cycles the switching will happen 

But how do I go about switching the order? would I just simply add a second function block ? 

if someone here could point me in the right direction I will greatly appreciate it. 

Thanks for your help, I added some sort of hysteresis and a low pressure alarm to it, TDE display for pressure and time/date just for kicks. I am sure more changes will come later. 

I am attaching the file with the small changes I made in case someone could benefit from it

EDIT 7/5/2024 

Added a new attachment 

• set points can be changed from the TDE
• Hour meter for each controller
• Adjustable offset for stage 1 and stage 2 air compressors
• unload valve control for reciprocating air compressors to purge the heads.