First of all, you need to understand their business relationship with you. This is the most vital thing. You can't just upgrade and tell them to pay or else they'd just go somewhere else.

When it comes to the expense of generating new business vs retaining, the latter one is cheaper. So, it's either you give them 2 or 3 months free for their annual subscriptions or provide them VIP access (considering you have tiers on your service) for added value.

You need to understand that they are the early adopters of your business model and this should not entirely be about the "immediate profit" but the long-term relationship.

If you need help in creating an organized onboarding for your previous customers, you can book a call with me here at Clarity.