On some exchanges where standard fields like INST_PHASE are not available, I tried to use Elektron Data Model to see which field could provide an alternative.
Unfortunately the model does not describe the specific values for each RIC / Exchange.
For example, OMXS30M0, The market is open when PRC_QL_CD value is 0 and closed when it is 94.
And the instrument closing auction starts when IRGVAL=11 and finishes when IRGVAL=14.
Although these qualifiers are partially documented in TRTH, it would be great if they were described in Elektron Data Model.