apyssjw nah, the route was a bit crap and windy - lots of tacks thrown down by Essex gammons objecting to road closures (probably Alistair and Dry Tinder) and there are quite a few blockages with u-turns. Definitely should do it once though - pretty cool finishing on Tower Bridge.
You done one before? You’ll be amazed how fast it is - it’ll be quicker and easier than you think with drafting. I did 3:52 last year - a crash split the group and I ended up split - worked hard for the last hour or so, but the early part was a doddle