The data frame fag_stratum_grts_calendar represents the designed sampling
unit calendar – across schemes – of the distinguished field activity groups
(FAGs). It has unique combinations of stratum, grts_address,
date_interval and field_activity_group.
Data frame.
The REP (revisitplan) workflow. See https://github.com/inbo/n2khab-mne-designs/tree/revisitplan/100_design_common/010_revisitplan.
fag_stratum_grts_calendar is derived from the scheme-specific FAG calendars
(object scheme_moco_ps_spsubset_fag_stratum_sppost_spsamples_calendar) by
eliminating spatiotemporal duplication and taking into account the highest
required FAG frequency across schemes.