Also, the old rule "if you don't use it, you will lose it" applies to any skill. So, the end goal should not be to get the certification, it should be to obtain the deeper level of skill. It is difficult enough to keep any skill set when you are unemployed, and unable to practice. It is doubly more so, if you crammed just to passed the
test, and isn't sure of the knowledge in the first place.
Remember, it is the skill that you want -- so how long it takes to get the certification should not be your highest priority.
Henry