PTP550 TDD Sync

Hi ..any body from Cambium can help on my below questions? Thanks.

if GPS sync is not deploy, what is the guard band needed between 2 colocated PTP550 links.

1)Assume using 40mhz channle (channel bonding not enable) on 5.8Ghz band

2) any issue to colocate 2 PTP550 links with 60Mhz channel (channel A 40Mhz + channel B 20Mhz) on 5.8 Band only?