[Avodah] matzah in mitzrayim

[daniel at kolberamah.org]

Quoting Saul.Z.Newman at kp.org:
> the barley was  destroyed  by  barad.   the  wheat  would  not  mature
> until  bnai yisrael  was at har sinai.
>  one  would  assume that   flour  from previous  years  was  used .
>
>  this  was  then  not  shmura  wheat  of  today  , unless  they  harvested
>  wheat and  put  in a water-guarded  place  a year  before  commanded to
> do  so.....

I thought that pshat was that they were not actually obligated in  
matzah the year of yetzias mitzriayim.  Otherwise, what does it mean  
that they didn't have time to make bread?  Why would they have been  
making bread in the first place, rather then matzah, unless there was  
no issur that year.  In which case there is no reason they should have  
used shemura flour.