yeast washing question?

so im fairly new to homebrewing, about to brew batch 11, and after my last two batches i decided to wash the yeast I had used previously. heres what I did.

made a starter for an amber ale i brewed using a wyeast 1056 american ale smack pack and pitched it into the amber, when the amber was done racked it off and pitched an ipa on top of the yeast cake, and of course the fermentation took off like a rocket, had to replace the airlock with a blow off hose, after the ipa was done racked it off and washed the yeast in accordance with the yeast washing illustrated instructions in this topic area of the forum. and i ended up with a large mason jar and five smaller mason jars that i put in the fridge, each of my jars has quite a bit more, probably double, of the creamy thick layer of yeast than do the pictures of the jars in the yeast washing illustrated thread. here are my questions:
-how long will the yeast be good for assuming I make a starter each time I reuse one of the jars?
-is there any problem with washing the yeast after it has been essentially been used three times 1. starter 2. amber ale 3. IPA?
-I ended up with three distinct layers in each jar, whats the best part to use? what part(s) should i discard before I repitch into a starter?
-is there anything else i am forgetting in accordance with anything i have done so far? is there anything wrong with my practices assuming my sanitation procedures were impecable?

thanks for all the input!

additionally, i will post pictures of my yeast washing results as soon as I get home to be able to take pictures of my jars, 6 in all.

also how many times can I rewash this yeast and save for later usage?

id like to keep wyeast 1056 on hand at all times since its expensive to buy liquid yeast cultures and I brew alot of ales and really have had good results with this yeast so far! also any additional details about what my best bet for repitching into a high gravity IPA would be appreciated as I plan to brew one this week!

Answers to your questions are probably in the sticky, but....

As long as it is sanitary, there is no real limit to how many generations you can repitch. You are likely to see some genetic drift after a while; either attenuation or flocculation will start to suffer.

If it's within a couple weeks, you won't need a starter at all if you have enough slurry. Up to four months or so, make a starter just to wake the yeast up. After that, approach it like you're rehabilitating your culture.

This is applicable to "normal" yeast. Weizen and Belgian yeasts are more fragile. They prefer to be top-cropped anyway.

Disclaimer: I am not a microbiologist. I don't know what I'm talking about.

I just used my first jar of washed Kolsch yeast to make a Blonde Ale. The jar I used had been in my fridge for 6 months before I used it. I poured off as much of the clear liquid as I could without losing any of the sediment. Shook the jar up and pitched into my starter. Starter took almost a day to really get going but the yeast did wake up and it made a nice looking starter. Pitched into the 5 gallons of Blonde Ale and it took off after 6 hours. Eventually had to put in a blow-off tube, which is uncommon for me. I still have 2 more jars of the Kolsch yeast and some PACMAN yeast.
Now that I know I can wash yeast and I have a good idea what styles of beer I like I'll start making jars of yeast. Right now yeast is my biggest cost, so saving $6 a smack pack will be very nice.

agreed yeast is the most expensive part of the process for me as well. did you use the yeast washing technique described in the wiki? if not what were your steps in detail to wash the yeast?

I used the technique as described on the wiki. Instead of pouring from the carboy/bucket I used my racking cane. I don't recall seeing a thick creamy-looking layer of yeast. I know there was a small layer, but as much as I have seen some people get. This may explain why it took a little while for my starter to get going.

It sounds like your process is good. Perhaps take one of your jars out and make a starter with it. If it takes off you know you've gotten viable yeast. Boil up some water and chill it to top off your jar and place it back in the fridge.