Maybe as an easy solution you can reset / clear almanac and other GPS data by calling dbus SetOptions() function for geoclue provider (NOTE: below script is not working for me but someone may fix it):
#!/usr/bin/python3
#
# Inspect Geoclue DBus API
# dbus-send --session --type=method_call --print-reply --dest=org.freedesktop.Geoclue.Providers.Hybris /org/freedesktop/Geoclue/Providers/Hybris org.freedesktop.DBus.Introspectable.Introspect
#
import dbus
# main starts here
if __name__ == '__main__':
bus = dbus.SessionBus()
obj = bus.get_object('org.freedesktop.Geoclue.Providers.Hybris','/org/freedesktop/Geoclue/Providers/Hybris')
api = dbus.Interface(obj, 'org.freedesktop.Geoclue')
options = dbus.Dictionary({dbus.String('NoCachedAidingData'): dbus.Boolean(True, variant_level=1)}, signature='sv')
api.SetOptions(options)
print('Cleared GPS data.')
(see https://github.com/mer-hybris/geoclue-providers-hybris/blob/master/hybrisprovider.cpp#L416 for reference)