This is where accurate nozzle based probes could help. Piezo probe on each nozzle in a multiple X carriage machine. G30 at start of print for each nozzle at bed centre and then each nozzle will be at the right height, the parked head won't interfere with the active one.
Simon Khoury
Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions