QB Issue Resolution:

Yes.  You can have up to 2 Accountant User on each company file.  Accountant users do not count towards the normal user limit and all users can be logged in doing work at same time.  Here is the breakdown by plan.

 

SimpleStart = 1 billable user + 2 accountant users

Essentials = 3 billable users + 2 accountant users

Plus = 5 billable users + 2 accountant users

Advanced = 25 billable users + 2 accountant users

Resolution for Issue 'Can more than one user be active in QuickBooks Online at the same time? It would be my clients admin user and myself (accountant user).' available: Yes (Solved).
Source: Intuit Community forum.

Can more than one user be active in QuickBooks Online at the same time? It would be my clients admin user and myself (accountant user).: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for accountant user
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Error Recovery for accountant user [Canada]
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