Confused about divvy membership pricing

I'm confused on the pricing conditions for divvy annual membership. The website (https://divvybikes.com/pricing) says:

> $143.90/year* ($99/year limited time offer available for new or returning members)

> $99 annual rate available for new and returning riders only. Existing members may not be eligible.

Why are existing members being charged more than new members? As an existing member I would expect to be "grandfathered" into a better rate, not locked into a worse rate.

What does a "returning" member mean - may existing members just cancel their membership and sign up again for the $99 rate?