Why so many Almanac Updates?

In the last 24 hours, my GPS receiver that is being used for
timekeeping has logged 3 changes to the almanac. All were week 86 but
the time started at 36 then went to 57 and ended up at 78 early this
morning. In the past, there was only entries about once a day in the
evening right around 0000 UTC. Is there any navsat movements
underway?

Tom


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Public Keys:
PGP KeyID = 0x5F22FDC1
GnuPG KeyID = 0x620836CF

Could be PRN10 related. On the USCG site it shows and UNUSUFN, but its
operational per NSTB (FAA WAAS) site.
Satellite repositioning are start-coast-stop operations, with the
start and stop operations in the order of hours with the coasting
lasting months. Almanac changes should only happen due to the start
and stop Delta Vs, plus some orbit refinements in between. The last
delta V event was over 2 weeks ago, so this shouldn't be the cause of
almanac updates.
Of course, an almanac update could happen with just minute changes.
GPS satellite orbits are always changing by tiny margins due to earth,
moon and sun gravity, sun flare activity, and for older satellites
reaction wheels that are beginning to miss behave, causing orbit
changes that take hours to be noticeable, but still small enough to
keep the satellite within specs.