This thread will become more interesting...
I live in Central Manchester and have got unlimited data plans from both Vodafone and Three.
For Vodafone without optimisation the ping ranges at 25-50ms, here's the best result after low-ping optimisation by doing the following:
1. Enabling 5G NSA of course! (5G SA mode is not available in our country just yet, so we need to rely a 4G cell for uplink).
2a. Selecting the least congested 4G cell for uplink (by band selection); and
2b. Disabling 4G Carrier Aggregation (so effectively we are receiving signals from one 5G + one 4G cell only).
3. Dedicated IP range (Re-connecting until we get the IP address with lowest ping
).
I do test ping to 1.1.1.1 and 8.8.8.8 routinely, they normally ranged at 9-15ms but will sometimes jump to 50-100ms (jitter). It's totally understandable as in the end we are in a wireless world, worth noting that even by fibre the lowest ping is 6-8ms depending how far you're away from the nearest internet exchange
.
Note that this result is not optimised for speed, in my area the fastest speed are 350-400Mbps indoors and 500-600Mbps outdoors at off-peak hours.
Happy to share my results for Three if anyone interested