These days, when ForgeRock sells subscriptions, it has an option to purchase Professional Service as a bundle. Free or not? I'm not too sure. It's part of price negotiation, I believe.
The ForgeRock Professional Service can be utilized as follows:
I think the original intend is to get customers up-to-speed with Open Identity Stack (OIS) deployment. This is especially helpful/applicable to customers who are more technical-savvy and would like to deploy OIS by themselves. High-level Architecture Workshop will be helpful.
Now, what if a SI who is well-trained in OIS is involved?
Customers, being customers, will want to cut cost. Always.
The worst case scenario is for a customer to ask the SI to cut-off a few man-days from implementation cost, since the customer can utilize Product Specialist Field Assistance. Wow! Unbelievable, isn't it? Nay, this should not happen at all and it really doesn't make sense. If customer insists, I think the best way is to walk away.
I think this Professional Service should be best utilized in Production, especially On-Site troubleshooting and Performance Analysis. There will be situations (or there had been?) where a site is badly deployed by a so-so System Integrator (SI) and is now causing production issues. It would be real hard for support engineers to provide remote support. An on-site troubleshooting comes in handy.