From Dave G3YMC

We discussed the subject of beacons,  band plans for them etc a long time
ago on this reflector.  I would like to remind us that unattended beacons
are not permitted under the license conditions on the 136kHz band, at least
not in the UK.  There is nothing to stop you putting attended beacons on,
though they would be classed as test transmissions.

A year ago when we first started on 136 quite a few stations beaconed in
the UK for a while.  With current level of activity they are apparently no
longer considered necessary and the practice has more or less stopped.

73s Dave