Seasonal Pricing / Themovation

What we've done is we have snapped the wp booking system into WooCommerce so that each calendar can be tied in with a product or in the case of a variable product, a sku.

You can create one product in WooCommerce and choose variable which allows you to set multiple prices for 1 product.

https://docs.woothemes.com/document/variable-product//

Once that is done you can add the sku replace of the ID like this:

wooproductsku="room_1_summer"

So altogether your shortcode would look something like this:

[wpbs id="1" form="1" title="no" legend="yes" start="1" display="3" language="auto" history="1" tooltip="1" month="0" year="0" selection="multiple" autopending="yes" weeknumbers="no" wooproductsku="room_1_summer"]

Then you create a calendar for each season and use the corresponding sku for that season rate. Something like this:
Summer Calendar:

[wpbs id="1" form="1" title="no" legend="yes" start="1" display="3" language="auto" history="1" tooltip="1" month="0" year="0" selection="multiple" autopending="yes" weeknumbers="no" wooproductsku="room_1_summer"]

Winter Calendar:

[wpbs id="2" form="1" title="no" legend="yes" start="1" display="3" language="auto" history="1" tooltip="1" month="0" year="0" selection="multiple" autopending="yes" weeknumbers="no" wooproductsku="room_1_winter"]

With the WP Booking System, you can create a calendar for each season, and then block off the dates that fall outside of that season, allowing the customer to only selected dates that fall within, coupled with the sku for that seasons rate, the calendars shortcode will add the room with the correct price.

You can also use the same calendar for both seasons, just make sure to add a unique wooproductsku to tell the calendar what pricing to use.