After updating server from 20w16a to 20w17a height map gets corrupted. At some places on  the F3 screen CH and SH values are ether over build limit or negative value. this is characterized by :

colons of rain going through blocks

Rain stopping at the reported CH value with no block present there

Inability to grow large trees at the locations with corrupted height(How i discovered the bug)

the Issue seems to be related to MC-139017 and MC-180566