A couple of days ago (19th)
A random antipodean on a rented e-MTB, taken the train to Rannoch, heading for Corrour.
I'd camped by the stream about 2 miles up the track from the B846.
If you want a long-ish loop you can head up Strath Ossian to Loch Laggan, along the S side of that to Ardverikie, head S past Loch Pattack to Ben Alder Lodge, up the side of Loch Ericht to Dalwhinnie, down the A9 cycle track to Dalnaspidal, then right along the side of Loch Garry and continue to join the Rannoch Station road at Craiganour Lodge.
There's about a mile of boggy track between the marked bridge over the River Pattack and the Loch, and mile of boggy path between the end of Loch Garry and the bridge over the river just before Duinish bothy. I wear SPD sandals, so I just stop at the first post-bog stream and rinse off my feet.
Caveat:
There were warnings earlier in the year about the A9 cycle track south of Dalwhinnie being closed for roadworks, with a shuttle bus running. It looked OK driving past, but I didn't ride it.