GC holder married B-2 in the USA-need I-130 advice

I have a Greencard and few months ago I got married here in the USA,
my fiancée was here on the B-2 visa. The she went home; we did not
file I-130 because I was told the processing time is 3-5 years and it
will be faster to me to become US Citizen and get her on K visa or so.

Now my wife is back into the USA on the same B-2 visa, and we are
looking for the possibilities to keep her here in a legal status until
I will get USC.

Someone who appears to be knowledgeable told me that, in our
situation, I can file I-130 for my wife simultaneously with the filing
of I-485 and this will allow my wife to stay here legally until I-130
will be approved or until I will get the USC. This person said this is
possible to do because my wife is already legally here in the USA.

All this sounds a bit strange for me and the immigration lawyer that
we consulted did not mention about this I-130/I-485 possibility,
although we did not ask directly about it.

Could this "I-130/I-485 plan" really work, i.e. legalize my wife's
presence in the USA? I have never heard about it and it sounds too
simple to be true.

Any comments are appreciated,

TIA,

Andrei