Found a fix for E-file error: 504 ( Gateway Timeout) Individual Filings
Assuming that your internet connection is good and that you are able to file other clients:
Remove all pdf attachments.
Clear the e-file under E-file/e-file support tools/clear return/return
Go into the Lacerte/21tax/IDATA/EF
Locate the client file NAME.IE1
Rename the file NAMEold.IE1
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