I've not been to Pembroke for years, and my guidebook is somewhat out of date. Can I just check:
1) Access to Range East doesn't require attending one of the briefings, and as long as they are not firing you're good to go? As far as I can see they're saying it should be fine this coming Fri/Sat/Sun/Mon?
2) There are plenty of accessible routes at, say, Saddle Head, Stennis Head and Flimston Bay, even when (as for this weekend) the tides are completely against you?