So how do you stop someone cancelling at end of January?

I definately beg to differ. Please refer to the Occupiers' Liability Act and specifically section 4 (1) and subsection 4 (3) (i). This legislation is why a fee for service organization like Canada's Wonderland is held to a higher duty of care than your would find with a provincal park.  A fee for service business would be held to "reasonable" care as detailed in section 3 (1) of the act.    Risks willingly assumed 4 (1) The duty of care provided for in subsection 3 (1) does not apply in respect of risks willingly assumed by the person who enters on the premises, but in that case the occupier owes a duty to the person to not create a danger with the deliberate intent of doing harm or damage to the person or his or her property and to not act with reckless disregard of the presence of the person or his or her property. R.S.O. 1990, c. O.2, s. 4 (1). Criminal activity (2) A person who is on premises with the intention of committing, or in the commission of, a criminal act shall be deemed to have willingly assumed all risks and is subject to the duty of care set out in subsection (1). R.S.O. 1990, c. O.2, s. 4 (2). Trespass and permitted recreational activity (3) A person who enters premises described in subsection (4) shall be deemed to have willingly assumed all risks and is subject to the duty of care set out in subsection (1), (a)  where the entry is prohibited under the Trespass to Property Act; (b)  where the occupier has posted no notice in respect of entry and has not otherwise expressly permitted entry; or (c)  where the entry is for the purpose of a recreational activity and, (i)  no fee is paid for the entry or activity of the person, other than a benefit or payment received from a government or government agency or a non-profit recreation club or association, and (ii)  the person is not being provided with living accommodation by the occupier. R.S.O. 1990, c. O.2, s. 4 (3).

The standard of care is the same whether it's government or non government in the court of law when it comes to tort related actions on the trails.    

Just to add to your comments, the elephant in the room is that governments are subjected to a different standard of care than a business is, whether it's for profit or not for profit. If the OFSC had their own permit again, they would be subjected to the same standard of care that you would expect of any other business. Be prepared to sign every corner, every washout, every tree; no more rustic trails. The law treats businesses that sell a service for a fee differently than a government license fee. Insurance costs would escalate and club volunteers and landowners would run away in fear of liability exposure. 

I ride motorcycles as well, my trousers and jacket have D30 Ghost armour, you don't even notice it's there.  It's flexible, but goes rigid when struck. https://www.d3o.com/partners/solutions/molded-parts/d3o-ghost-l2-limb-protectors/    I'm surprised Tekvest is still using old tech, their vests are made of closed-cell foam and plastic laminate armour.   I'm considering getting something, but I'd rather have modern tech protecting me.