From FIXwiki

FIX Message TradingSessionStatus (MsgType=h)

MsgType	FIX Specification	First introduced	Deprecated
MsgType=h	PreTrade messages - MarketStructureReferenceData	FIX.4.2

The Trading Session Status provides information on the status of a market. For markets multiple trading sessions on multiple-markets occurring (morning and evening sessions for instance), this message is able to provide information on what products are trading on what market during what trading session.

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Notes

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