Jen pro případ, že by to něčemu pomohlo: nebude to ani tak otázka LTE jako buď přímo T-Mobile, nebo naopak na druhém konci u cloudflare. Tohle vidím teď právě z T-Mobile VDSL, 100/10Mbs:
ping -c 10 production.cloudflare.docker.com
PING production.cloudflare.docker.com (104.18.123.25): 56 data bytes
64 bytes from 104.18.123.25: seq=1 ttl=54 time=59.957 ms
64 bytes from 104.18.123.25: seq=2 ttl=54 time=58.600 ms
64 bytes from 104.18.123.25: seq=3 ttl=54 time=59.763 ms
64 bytes from 104.18.123.25: seq=4 ttl=54 time=58.135 ms
64 bytes from 104.18.123.25: seq=5 ttl=54 time=59.039 ms
64 bytes from 104.18.123.25: seq=8 ttl=54 time=58.520 ms
--- production.cloudflare.docker.com ping statistics ---
10 packets transmitted, 6 packets received, 40% packet loss
round-trip min/avg/max = 58.135/59.002/59.957 ms