@Gengar I have created a ticket now to set the PTR records. But going back to your original issue:
"host -t PTR <ipv6> 127.0.0.150 always fails instantly." This works just fine on my VPS. Maybe you have some firewall rules? I just allowed everything incoming in firewall.
ubuntu@ov-9503b4:~$ host -t PTR 45.55.2.141 127.0.0.150
Using domain server:
Name: 127.0.0.150
Address: 127.0.0.150#53
Aliases:
141.2.55.45.in-addr.arpa domain name pointer my.cloudron.io.
ubuntu@ov-9503b4:~$ host -t PTR 2604:a880:1:4a::2:7000 127.0.0.150
Using domain server:
Name: 127.0.0.150
Address: 127.0.0.150#53
Aliases:
0.0.0.7.2.0.0.0.0.0.0.0.0.0.0.0.a.4.0.0.1.0.0.0.0.8.8.a.4.0.6.2.ip6.arpa domain name pointer my.cloudron.io.