ILR 5 year route FLR(M) applicant but outside U.K for 1.5 year

[bhoopalr]

I am British Citizen and my wife on dependent visa FLR(M)

She got initial visa in July 2013 and due to work reasons moved to Dubai for 1.5 year(Jan 2014 till May 2015) then came back to U.K and living together since then.

I applied for extension in 2016 March and visa was extended. Can we apply for ILR now or do we need another extension as she lived outside U.k for more than 180 days .

One of friend wife was in India for delivery for more than 1 year and she got an ILR. Only difference in my case is we both are outside U.K and no medial reason for us.

Could you advise can we apply for ILR are there any specific rules for FLR(M) dependent to stay in U.K continuously for 5 years.

Thanks for your help and advise.