My observation on eBay bikes and major components is that most make very significant gains in the last day and even last hour. Forks rocketing from no one bidding at £20 at 7am to £100 at 8pm and £200 or so by sale time at 9pm is not unusual.
It’s a bit like chicken, people pulling sales because it’s not making enough had a reserve price in mind but were too cheap to pay for it.
OP, unless you doorstep seller with a buy it now offer and roll a test ride in, you’ve blown this one by posting it and your top limit.
In future, decide what you’re happy to pay , bid less and make a last minute decision about raising your bid close to end time. Expect a lot of frustration unless your tastes are for severely unpopular bikes.