Depends on what you mean by Spark. Spark capable devices are able to connect to LTE on bands 25, 26, and 41. Band 25 is currently live. Band 26 will be live very soon. Band 41 (the "fast" Spark band) will be further into the future.
Band 41 is currently being deployed in existing Wimax markets. Indianapolis was not a Wimax market, so we are further down the list for band 41 awesomeness.
If you own a triband device, you will benefit greatly from band 26 as it will be less burdened at launch due to many less triband devices on the market.
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