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Not only am I crazy I am blind too.

Other than TPC frames there are 3 other frames introduced by 802.11h. Defined in section 7.4 of the amendment:

1.The Measurement Request frame uses the Action frame body format and is transmitted by a STA requesting another STA to measure one or more channels.

2.The Measurement Report frame uses the Action frame body format and is transmitted by a STA in response to a Measurement Request frame or by a STA autonomously providing measurement information.

3.The Channel Switch Announcement frame uses the Action frame body format and is transmitted by an AP in BSS or a STA in an IBSS to advertise a channel switch.

I believe you are asking about number 3 the Channel Switch Announcement Frame. This frame is used to indicate to all associated Stations the channel to which the AP is switching and how long the AP will remain on the current channel.
I may not have been clear enough before, or I could be wrong again. Either way thanks for forcing me to read 802.11h. It was a good read.