One can be on only one immigration status at a time!
Frequently, foreign nationals in the United States apply for more than one immigration benefits, one after the other.
Successive visa and permanent residence applications under different categories are permissible and is done very frequently so that the foreign nationals can stay in U.S. and continue with their lives peacefully. However, at a time, the foreign national could hold only one immigration status.
While each change of status or extension application involves necessary additional expense, the benefits that comes with each such status can not always be enjoyed in combination because you are a worker either under H1b or under L1 status. Or for immigration status you are either a student or a spouse or a foreign national employee.
When the benefits attached with more than one status are simultaneously enjoyed, what you have at one hand is one bigger immigration issue.