The information on availability is an estimate and is subject to change. If you act relying on that estimate, you accept the risk of the information changing. There are only very limited circumstances where the law gives you a cause of action based on you placing detrimental reliance on information provided outwith a contract. These circumstances do not fit the criteria, as you were never promised
a fibre based service would be available by a given date.
As MrSaffron sometimes says, you should never commit to renting or buying a property based on future availability information - only what is available to order now. Obviously the commitment involved in buying equipment is much less than renting or buying property, but I personally wouldn't buy equipment for a service I couldn't order today unless I was changing equipment anyway and could choose equipment supporting later standards than I needed immediately (e.g. ADSL2+ and VDSL2 support when the current service was ADSL2+).
Being blunt about it, if you think tens of thousands of pounds of work will be done any quicker (and, for that matter, at all) because you bought equipment likely costing less than £200 two years ago, I suggest your position is unrealistic.
Indeed, the complaints to the Advertising Standards Authority and direct to Openreach from people who weren't prepared to accept the information Openreach publicised about fibre deployment was a provisional estimate is a key reason why Openreach is now very coy about future deployment plans.