Desk research against primary sources. Figures are traced to the issuing UAE authority and linked on the page.
The two routes out of a probation period are not interchangeable, and which one applies depends on where you are going next rather than why you are leaving. Leaving the UAE altogether is the simpler case. Moving straight to another UAE employer brings a second employer's obligations into play, and in practice that can slow down or complicate an otherwise straightforward exit if the new employer is unwilling or slow to settle the compensation MOHRE requires.
Because the period has a hard ceiling and cannot be extended, an employer cannot keep you on probation terms indefinitely by simply not confirming your status — once the maximum has passed, ordinary termination rules apply whether or not anyone formally told you probation was over. If you are unsure which regime currently governs your contract, check the date probation started against your contract rather than asking your manager, whose informal answer is not what MOHRE will look at in a dispute.