Unsupported. Brought a handbottle and four gels. Started a bit before the El Cerrito del Norte BART on the greenway, also did an extra lap around the block at the end to hit 50k. So actual time would be a little bit shorter but I'll go with 3:50:08. It's a solid time. If I'd started earlier, would have lost less time to stoplights.
7:24 elapsed pace, 7:11 moving pace.
Gorgeous day. Happy with the performance after doing a hill workout yesterday. Hoping someone takes this further down soon!