Freshdesk-> Service Desk migration- input required

[Books XTM]

Hi guys, 

I'm PM at XTM International, also responsible for management systems being used in our development process..
In our company we're considering migration from our current client support system, which is Freshdesk to Service Desk, as it would be much more integrated with Jira, that we use internally for development process management.

My assumption is that we would not be first ones to do that, so I'm contacting you to get as much technical information, as possible about the migration process, as I need to report to the board, so we can make a final decision. 
We've been with Freshdesk for 9 months now, but we struggle with systems incompatibility. 
Please, provide your feedback about potential cost and timeline of such migration.
We have currently couple of thousands of users in the system and as many tickets to be migrated. I guess tickets in FD can be exported as JSON. No major customization has been made to the system.
We need details on following:
- potential cost involved
- timeline
- clients management (we need to keep current structure and assignment of the tickets)
- user management- we noticed, that each time ticket is submitted in SD, a user is created in Jira, making user database grow huge and possibly making user management more difficult (we want jira users to be separated from SD "external" users, so clients submitting tickets in that case.

Please, deliver as much details, as possible, as we're running on tight schedule.
This is initial email, I'm hoping for further discussion, as we progress with details.

Please, respond to my personal email address: dwaloszczyk@xtm-intl.com
Prompt reply would be highly appreciated.

Kind regards,
Daniel Waloszczyk

[Nic Brough -Adaptavist-]

We're not support here, we are a community of end-users.

Even if we were, Atlassian does not do that sort of work.  I would strongly recommend you engage one of their solution partners for this.  Visit https://www.atlassian.com/partners/search?page=1 for help with selecting some to talk to.

Also, as I work for one of them, and see this sort of question a lot, the short answer is "you are going to need to give us a lot more detail before you can get a good estimate", so be prepared for whomever you engage to ask a lot more questions.