Looking at the past few years of observation data, it appears that (1) it is possible to sight the first day’s Hilal on the UK horizon throughout the year (if a real effort is made), (2) attempting to sight the Hilal on the UK 29th, shows it will triple the number of 29th day’s sightings compared to looking (in the UK) on Morocco 29th (see YouTube Video). [charts] [View Observation Results] [UK Moon Sighting Fatawa]
Note: a lunar calendar is self-correcting and does not accumulate errors. For example, if a 29th-day sighting was missed (eg. 3/3/2022), leading to completing 30-days, then the following month's 30th (eg. 2/4/2022) will become 29th, without affecting the subsequent months!